U.S. fuel prices surged on Monday as two more Gulf Coast refiners cut output and a third considered reductions, leaving more than 13% of the country's refining capacity offline after Tropical Storm Harvey flooded plants and shut seaports.

The storm swung back over the Gulf of Mexico on Monday and was expected to bring another 10 in to 15 in (25 to 38 cm) of rain to the Houston area and up to 8 in as far east as New Orleans, the National Weather Service said.

Lyondell Basell Industries' Houston refinery early on Monday also cut output by half to conserve crude supply, other sources said.

Meanwhile the nation's largest plant, Motiva Enterprises' 603-Mbpd Port Arthur, Texas, refinery was considering shutting due to high water on the plant grounds and running with essential personnel only, two sources said.

The profit that refiners make per barrel of gasoline jumped as high as 21% in the first trading day following Harvey's landfall near Corpus Christi, Texas, late on Friday, as fears of short supplies gripped the market.

Gasoline for immediate delivery in the Gulf Coast hit five-year highs, traders said, while U.S. gasoline futures jumped as much as 7% to $1.78 per gallon, the highest since late July 2015.

In total, 2.45 MMbpd of US refining capacity was shut due to Harvey, which knocked out four refineries in South Texas before bringing flooding rains to plants near Houston.

Nearly 19% of oil production in the Gulf of Mexico has been shut, the US Department of the Interior said on Monday.

Marathon spokeswoman Stefanie Griffiths declined to comment. Lyondell and Motiva did not reply to requests for comment.

Oil prices fell as the refinery closings reduced demand, with US crude futures dropping by more than 3% on Monday.

Among other Gulf Coast refiners, Exxon Mobil's 362.3 Mbpd Beaumont, Texas, refinery has cut production, the company said. It did not provide additional details. Earlier, Exxon halted production at its 560.5 Mbpd Baytown, Texas, plant.

Valero Energy's 335 Mbpd Port Arthur, Texas, refinery is running at or near maximum capacity but contending with flooding in the plant, sources said on Monday. Valero confirmed the plant is running, but has not commented on further.

In the area where the storm first hit, Citgo Petroleum's refinery in Corpus Christi is preparing to begin its restart process as early as on Wednesday, sources said. A spokesperson did not reply to requests for comment.

Two other refiners who shut plants in the region, Valero and Flint Hills Resources, did not respond to requests for updates on their operations there.